Freeze Damage Uncovered: An EDT Case Study on COVID-Era HVAC Changes

portrait photo of David

David S. Williams, P.E., CFEI

When COVID-19 changed the way facilities managed airflow, one commercial building quickly modified its HVAC system to bring in more outside air. The intent was good: improve circulation and reduce viral spread. Unfortunately, those changes had unintended—and costly—consequences.

To meet evolving health guidelines, the facility made on-the-fly modifications to its HVAC system. More outside air was brought in, but in the process, critical freeze protection measures were bypassed. What seemed like a simple adjustment created the perfect setup for a system failure to occur.

The Freeze Event 

When freezing temperatures hit, the consequences were immediate. Coils and piping froze, cracked, and caused significant water damage. The facility quickly faced a system shutdown and a costly insurance claim.

EDT Investigates

That’s where Engineering Design & Testing Corp (EDT) stepped in. David Williams, P.E., CFEI, led the forensic investigation to uncover the truth about what really happened. His analysis included:

  • Evaluating the HVAC system’s original freeze protection design
  • Reviewing documentation of the COVID-related airflow changes
  • Assessing how equipment exposure and temperature controls factored into the incident

David found the root cause. The unvetted modifications upset the delicate balance of the HVAC system. By bypassing built-in freeze protection, cold air flooded system zones unchecked. With no tempering or automatic shutdown response, the equipment was left defenseless and ultimately failed.

Key Lessons for Insurers and Facility Managers

EDT’s findings clarified that the damage was not due to inherent design flaws but rather to unvetted modifications outside the manufacturer’s specifications. The report supported the insurer’s ability to evaluate coverage and subrogation options.

The takeaway was clear; the HVAC system wasn’t inherently flawed. Instead, the damage stemmed from hasty, unsanctioned modifications made outside of the manufacturer's specifications. EDT’s findings gave the insurer the clarity needed to properly assess coverage and subrogation options.

Why EDT

Incidents like this highlight how easily well-intentioned modifications can have costly consequences. EDT’s forensic engineers bring clarity to complex failures by uncovering the true root cause. With decades of experience across mechanical systems, HVAC, and building operations, EDT provides insurers and facility owners with the insights they need to evaluate claims, identify liability, and prevent future losses.

If you’re facing a complex system failure and need objective answers, assign a file today to get started.

 

About the Author

David S. Williams, P.E., CFEI is a consulting engineer with our Seattle-Tacoma Office. Mr. Williams provides consultation in the areas of mechanical component failure/fracture analysis, combustion systems, boilers, rotating power equipment, fluid flow control and waste gas handling systems, motor control, and sheet metal stamping equipment. You may contact David for your forensic engineering needs at dwilliams@edtengineers.com or (253) 345-5187.

Back to Blog